fossil
Orthoceras Fossil
Orthoceras sp. (Extinct genus of nautiloid cephalopod)
Polished finish, black limestone matrix with white/grey calcified fossils. Hardness: 3-4 (matrix). Features conical shell structures with visible septa (internal chambers).
- Hardness
- 3-4 (matrix)
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Physical properties
Polished finish, black limestone matrix with white/grey calcified fossils. Hardness: 3-4 (matrix). Features conical shell structures with visible septa (internal chambers).
Formation & geological history
Formed during the Ordovician period (approx. 400-485 million years ago) in marine environments. These specimens are most commonly sourced from the Erfoud region of Morocco.
Uses & applications
Informational/educational displays, decorative paperweights, jewelry (pendants/cabochons), and metaphysical collecting.
Geological facts
The name 'Orthoceras' means 'straight horn,' referring to its characteristic long, conical shell. They are ancestors to the modern squid and lived inside these shells while moving through the ocean.
Field identification & locations
Identified by the distinct white conical shapes against a dark grey or black background. Frequently found in large 'death beds' within limestone slabs in North Africa.
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